[illia-haidar]

Fixes #1276

For a query without a template (sql.unsafe(), sql.file(), internal queries), the origin getter falls through to originStackCache.set(this.strings, this[originError].stack). There this[originError] is false and this.strings is a new array per query, so every failure (queryError() reads origin) adds an entry that is never used again. This returns '' early for such queries.

• The return value is unchanged. The getter already returned '' for them; only the cache entry goes away.
• Tagged queries and debug: true keep their current branches.
• A failing unsafe() still reports its SQLSTATE, query and stack.

The new test, Failing queries without a template add nothing to the origin cache, runs a failing sql.unsafe() three times. It counts Map.prototype.set calls keyed by that query's strings array, without measuring memory.

• It fails without the change (0 != 3).

Locally, against PostgreSQL 17:

• tests/index.js (ESM) passes on Node 26.0.0 and 24.22.1, all 265 tests;
• the CJS build passes too;
• eslint src tests is clean.

This is independent of #1275: it merges with it without conflicts, and the two together pass the suite (266 tests). cjs/, deno/ and cf/ are left for the build step.